In today's electronic technology, integrated circuits are currently built by a process consisting of multiple steps of lithography followed by deposition and/or etching procedures. Each step requires a significant amount of time to perform, and the waiting time between steps can be long. The total time required to produce a batch of devices can be weeks. Thus, the process is time-consuming, and in addition, the environmental and safety concerns associated with toxic chemical materials that are usually involved and released during the process ultimately make the process very expensive.
Electrically conducting organic polymers have been of scientific and technological interest since the late 1970's. These relatively new materials exhibit the electronic and magnetic properties characteristic of metals while retaining the physical and mechanical properties associated with conventional organic polymers. These polymers are conjugated systems that are made electronically conducting by doping. Even though conducting polymers have the potential for a large number of applications in such areas as electrostatic charge/discharge protection, electromagnetic interference shielding, resists, electroplating, corrosion protection of metals and ultimately metal replacement, the lack of processability of conducting polymer materials (because of their insolubility in the conducting form), infusibility, and poor mechanical properties, e.g., ductility, have slowed down their emerging commercial applications.
To date, there have been only two interesting demonstrations of using conducting organic polymer in the fabrication of printed circuit boards through direct metallization process on non-conducting substrates. The primary problem with those two processes is that they still use conventional lithography methods and through-hole plating techniques, and they are still time-consuming because of the number of steps and long waiting time between steps.
Thus, what is needed to produce high quality circuit boards at competitive prices is a process that keeps production costs down, and this in turn means less consumption of environmentally toxic chemicals, reduced number of manufacturing steps, shorter process times, and a greater need for automation.